The present application relates to a pump which is formed of rotating parts, which can operate without blades.
Rotating pumps often use blades or propellers to press a fluid in a desired direction. These blades can subject the liquids to harsh impact.
For instance, if the pump is used to pump blood, then the blades can actually cut or otherwise damage certain blood cells, resulting in hemalysis injuring the blood. In other cases, the blades can cause cavitation and produce undesired gas bubble turbulence in the fluid.
The present application teaches a bladeless pump for fluid flow. While the pump has many different applications, one application of the pump is for use in pumping blood and other multiphase flows of body fluids. Other uses include thrust generation and propulsion.
One aspect of the application discloses a pump with a moving part that has a substantially smooth outer surface.
Other aspects include that outer surface having a substantially constant outer diameter. The moving part can be a rotating shaft held captive within an outer cylinder. The inside surface of the outer cylinder includes ridges thereon which are tilted a specified angle. The optimum angle is believed to be 45 degrees. However, any angle a, between (0 less than a greater than 90 degrees) can produce a pumping effect.
A specified relatively small distance is maintained between the rotating substantially smooth inner surface, and the inside of the outer shell. This small distance can preferably be an amount that prevents substantial leakage of fluid between the ridges.